We have great news to report for those with a Galaxy S4 powered by Exynos.   According to GSMArena, Samsung will be releasing the Android 4.3 update on the Galaxy S III next month, while the Galaxy Note II will be getting it in December because of the many S-Pen features that need to be ported.  For more information see below.

Here is the complete change log:

• OpenGL 3.0 Support
• GALAXY GEAR Support
• TRIM Support (Makes the device much faster)
• ANT+ Support
• Samsung KNOX Implementation (KNOX bootloader and dedicated application)
• Samsung Wallet comes pre-loaded
• Improved RAM management
• Improved Display colour reproduction (Display looks much sharper than before)
• Improved TouchWiz Launcher (Much less launcher redraws and less lag)
• New Samsung Keyboard
• New Samsung Browser (Full screen by default, new tab interface and more)
• New Reading Mode (Optimises display for reading, used by only a few specific applications)
• New Camera firmware
• Minor UI tweaks (Contacts app, Flashlight Widget, dialog boxes etc)

Here's where you can get the latest update if somehow you can't get OTA update

https://live.samsung-updates.com